The puzzle expert Will Shortz says that a mathematician
named Douglas Hofstadter came up with the following
word puzzle:

Think of a four-letter common noun that names
a tiny animal. Now change the second letter of
the noun to the next letter in the alphabet. What
larger animal, also four letters long, do you
come up with?

HINT:Don't look at this hint if you
don't need it.The name of each animal begins with the letter
g.